A principle that many have found attractive is one that goes by the name “'Ought' Implies 'Can'.” According to this principle, one morally ought to do something only if one can do it. This essay has two goals: to show that the principle is false and to undermine the motivations that have been offered for it. Toward the end, a proposal about moral obligation according to which something like a restricted version of 'Ought' Implies 'Can' is true is floated. Though (...) no full-fledged argument for this proposal is offered, that it fits with a rather natural and intuitive picture of the structure of morality and seems to explain certain salient features of the debate over whether the principle is true, goes some way toward recommending it. (shrink)